A standard procedure used in the treatment of endovascular diseases is the placement of medical devices, such as embolic coils, stents, and dilation balloons, among others, at a desired or targeted site (e.g., aneurysm, etc.) within a patient. The delivery of such a medical device has typically been accomplished by a variety of means, including the use of a catheter along with a pushing wire or a means of injection, as well as a system to which the device is attached during delivery and detached once the device is proximate to the targeted site. These medical devices usually have a contracted shape that allows them to pass through the lumen of the body vessel and an expanded shape that occurs after being deployed at the targeted site.
One specific example, of such a medical device is an embolic or occlusive device that is placed within a body vessel or vasculature of the human body to filter the flow of blood through a vessel in the vasculature or to block the flow of blood within a defect in the vessel, such as an aneurysm. One example among many widely accepted types of occlusive devices is a detachable helical wire coil whose coil windings are sized to engage the wall of the vessel. Detachable coils are usually selected when the anatomy is especially distal and tortuous, a risk of coil displacement exists, or a very precise placement of the coil is required.
One example of a detachable medical device delivery device is a pusher member including two polarizable wires that each include a polarizable tine. The two polarizable tines can be polarized to engage a proximal opening of the medical device, or they can be biased into engagement with the medical device. The two tines can then each be polarized such that they are drawn together to release the medical device.